The toxicity of lead has been recognized for many years, but the widespread use of the metal throughout history means that we’ll be forced to deal with lead and its health consequences for the foreseeable future. Lead poisoning causes many health problems, including damage to neurological systems. The developing brains and nervous systems of children can be severely harmed if their lead levels are too high.

Most children today are tested for lead poisoning, but the vast majority of those tests are based on blood samples. Blood tests reveal elevated lead levels in the blood. Here’s the problem: Lead is absorbed by brain and other tissues, and blood tests aren’t as good at registering high lead levels in the brain. Plus, blood tests reveal only very recent exposure.

Federal legislation was enacted in the 1970s to remove lead from paint and fuel, and many people assume that lead levels have dwindled as a result. That’s simply not the case because lead doesn’t go away — it’s a very persistent material.

What are the major sources of lead toxicity today? Lead can be found in all sorts of places, including the following:

  • Lead paint: Most of the paint used on homes prior to 1960 contained dangerously high levels of lead, and lead was still present in paints used on homes up to the late 1970s. Some estimates indicate that 10 million pounds of lead are still on painted surfaces in the United States. As many as 6 million homes, which house about 2 million children, have surfaces covered in paint that includes lead.

    When you think of lead paint, you may think only about painted interior and exterior walls of old houses. Unfortunately, that’s just the tip of the iceberg. Lead paint can be used on all kinds of surfaces, and believe it or not lead is still used in some paints today.

    Although it seems unthinkable, some toy manufacturers still use lead paint on toys, even though it’s illegal. To get a feel for the scope of this problem, run a search for “toy hazard recalls” on the U.S. Consumer Product Safety Commission’s Web site.

  • Water supplies: Some older homes have plumbing that includes lead or lead soldering. That lead can leach into your drinking water, and the problem is more common than you may think. Some researchers indicate that as many as 16 percent of household water supplies have dangerous concentrations of lead.

  • Other sources: Millions of tons of lead are produced every year for industrial and commercial uses, and the toxin ends up in many items. For example, the glazing used on some types of pottery contains lead, and the supplies used in creating stained glass can be lead-rich, as well. And you know that antique lead crystal decanter that your grandmother passed down to you? It’s called lead crystal for a reason. Many candles also have lead core wicks.

For more information on lead and lead poisoning, visit the EPA’s lead information page.